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Many such sites have hominin bones, teeth, or footprints, but unless they also include evidence for tools or tool use, they are omitted here. This list excludes tools and tool use attributed to non-hominin species. See Tool use by non-humans. Since there are far too many hominin tool sites to list on a single page, this page attempts to list ...
The earliest alloy used for the production of tools was arsenical bronze/copper, of which e.g. the tools used at Old Kingdom Giza were manufactured. [19] This alloy is harder than the "pure copper", presumed to be used by ancient Egyptians in earlier, now outdated works. [20] In the New Kingdom, the predominant practical alloy was tin bronze. [21]
The first devices used for measuring the position of the Sun were shadow clocks, which later developed into the sundial. [8] [note 1] The oldest known sundial dates back to c. 1200 BC (during the 19th Dynasty), and was discovered in the Valley of the Kings in 2013.
The screw pump is the oldest positive displacement pump. [1] The first records of a water screw, or screw pump, date back to Hellenistic Egypt before the 3rd century BC. [1] [3] The Egyptian screw, used to lift water from the Nile, was composed of tubes wound round a cylinder; as the entire unit rotates, water is lifted within the spiral tube to the higher elevation.
The use of wind to provide mechanical power came somewhat later in antiquity. The Babylonian emperor Hammurabi planned to use wind power for his ambitious irrigation project in the 17th century BC. [16] Hero of Alexandria (Heron) in first-century Roman Egypt described what appears to be a wind-driven wheel to power a machine.
The light mill is uniformly coated by gold nanocrystals, which are a strong light absorber. Upon exposure, due to geometric effect, the convex side of the vane receives more photon energy than the concave side does, and subsequently the gas molecules receive more heat from the convex side than from the concave side.
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The Stone Age is a broad prehistoric period during which stone was widely used in the manufacture of implements with a sharp edge, a point, or a percussion surface. The period lasted roughly 2.5 million years, from the time of early hominids to Homo sapiens in the later Pleistocene era, and largely ended between 6000 and 2000 BCE with the advent of metalworking.